WM8580AGEFTRV WOLFSON [Wolfson Microelectronics plc], WM8580AGEFTRV Datasheet - Page 38

• Manufacturer Part Number: WM8580AGEFTRV
• Description: Multichannel CODEC with S/PDIF Transceiver
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

WM8580
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Figure 23 shows the application and release of MUTE whilst a full amplitude sinusoid is being played
at 48kHz sampling rate. When MUTE (lower trace) is asserted, the output (upper trace) begins to
decay exponentially from the DC level of the last input sample. The output will decay towards V
with a time constant of approximately 64 input samples. If MUTE is applied to all channels for 1024
or more input samples the DAC will be muted if IZD is set. When MUTE is de-asserted, the output
will restart immediately from the current input sample.
All other means of muting the DAC channels will cause a much more abrupt muting of the output.
This abrupt muting is referred to as an analog mute and it will switch the analog outputs immediately
to VMID.
DE-EMPHASIS MODE
A digital de-emphasis filter may be applied to each DAC channel. The de-emphasis filter for each
stereo channel is enabled under the control of DEEMP[2:0]. DEEMP[0] enables the de-emphasis
filter for DAC 1, DEEMP[1] enables the de-emphasis filter for DAC 2, and DEEMP[2] enables the de-
emphasis filter for DAC 3.
Table 27 De-emphasis Register
Refer to Figure 41, Figure 42, Figure 43 and Figure 44 for details of the De-Emphasis modes at
different sample rates.
DAC OUTPUT PHASE
The DAC Phase control word determines whether the output of each DAC is non-inverted or inverted
Table 28 DAC Output Phase Register
REGISTER ADDRESS
REGISTER ADDRESS
DAC Control 3
DAC Control 4
R17
R18
11h
12h
BIT
2:0
BIT
5:0
4
DEEMP[2:0]
DEEMPALL
PHASE
LABEL
[5:0]
LABEL
DEFAULT
111111
DEFAULT
000
0
Controls phase of DAC outputs
0 = inverted
1 = non-inverted
PHASE[0] = 0 inverts phase of
DAC1L output
PHASE[1] = 0 inverts phase of
DAC1R output
PHASE[2] = 0 inverts phase of
DAC2L output
PHASE[3] = 0 inverts phase of
DAC2R output
PHASE[4] = 0 inverts phase of
DAC3L output
PHASE[5] = 0 inverts phase of
DAC3R output
DEEMP[0] = 1, enable De-
emphasis on DAC1.
DEEMP[1] = 1, enable De-
emphasis on DAC2.
DEEMP[2] = 1, enable De-
emphasis on DAC3.
DEEMP[2:0]
1 = De-emphasis enabled on all
DACs
De-emphasis mode select:
0 = De-emphasis controlled by
DESCRIPTION
DESCRIPTION
PD Rev 4.3 August 2007
Production Data
MID
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